1. Field of the Invention
This invention relates to improvements in anchoring rods installed in poured concrete, and the like, and more particularly, but not by way of limitation, to adhesively secured or grout-in anchor rods embedded in concrete or the like.
2. Description of the Prior Art
The anchoring of rods in poured concrete structure, such as a concrete pad, or the like, has long been a problem, and the use of adhesively secured anchor rods in such installations is a relatively new innovation in the art. The adhesively secured anchor rod system as presently available normally comprises the drilling of a bore in the concrete structure wherein the anchor is to be set. A sealed capsule of adhesive material is inserted or dropped into the bore, the sealed capsule usually containing the two components of the adhesive material. The anchor rod is inserted into the bore having the capsule deposited therein, and the rod is moved longitudinally into or through the bore in a twisting motion whereby the capsule is broken and the two ingredients contained therein are stirred together as the anchor rod moves downwardly in the bore. One such system incorporates the use of Parabond capsule anchors (Parabond is a trademark of Emhart) and is shown in advertising brochures of Molly Division Headquarters, the brochures being dated March, 1980. A clamping member for an adhesively secured anchor rod is shown in the Schiefer et al U.S. Pat. No. 4,193,256, and the Rausch U.S. Pat. No. 4,129,007 relates to an adhesively secured anchor of the type in use today. The Wiggill U.S. Pat. No. 3,925,996 discloses an anchoring resin cartridge system which may be utilized in the adhesively secured anchor rod systems. Other rod anchoring systems or devices are available, such as that shown in the Schuermann et al U.S. Pat. No. 3,188,815 and the reissue U.S. Pat. No. Re. 25,860 corresponding thereto. The device disclosed in the Schuermann et al patent includes an anchor bolt having threads in combination with an expanding sleeve, but is in an entirely different environment and for a completely different purpose than the adhesively secured anchor rods.
The presently available devices and systems for adhesively anchoring rods in a concrete base, or the like, have certain disadvantages in that it is frequently difficult to ascertain the depth of embedding of the anchor rod, and the usual threaded portion of the anchor rod disposed within the concrete may pull out of engagement therewith upon the application of sufficient longitudinal force on the exposed portion of the rod. In addition, the usual threaded portion of the anchor rod which is disposed within the bore is frequently of a relatively fine thread size and may not provide an efficient mixing of the ingredients of the adhesive, resulting in a reduction of the effectiveness of the adhesive material whereby the anchor rod may "back out" of the bore.